Cylinder or tube.



PATENTED MAR. 10, 1908'.

R. J. HOFFMAN.

CYLINDER 0R TUBE APPLIOATION FILED MAY 10.1907.

ROSS .l. HOFFMAN, F BRADFORD, PENNSYLVANIA.

CYLINDER OR TUBE.

b Specification of Letters Patent.

Patented March 10, 1908.

Application filed May 10, 1907 Serial No. 372,928.

0 poses.

1n the pump now in use for ,oil. wells, the agent through which power isapplied to the pump, is an, by means of, which several.

pumps, in wells more or less remote from each other,may be operated froma central source of power. This agent requires alarge cylinder,'which,as heretofore made is expensive, these cylinders being cast andsubsequently lined, to give proper surface for the piston.

My invention herein described, is designed for the lpurpose of avoidingthis expense, and- I find t at by my construction a perfect and durablecylinder can be easily and cheaply produced.

In the accompanying drawings Figure 1 represents a central longitudinalsection of a cy i . which may be very thin.

"edges, on the mandrel.

nder made according to my invention,

and Fig. 2 is a side elevation of a tubing made according to myinvention. Fig. 3 is a detail sectional view'of part of the cylinder ortube taken transversely thereof.

In carrying out my invention, I provide a mandrel, of proper length andof a diameter exactly equal to the required interior diameter of thecylinder to be made. Upon this I wrap a sheet of metal, preferablybrass, and I This sheet is cut to dimensions required, was to fitclosely at all points, and to bring together the abutting Upon the sheetmetal so ap lied, I closelycoil suitable wire, with the fo ds thereofcontiguous, and extending from end to end, so as to form a continuouslayer of wire over the sheet metal. As the Wrapping proceeds I applysolder to the Wire which solder is sweated into the crevice between thecoils and into the spaces between the wire and the sheet metal, thusformin a solid combined shell. This solder I holds t e wire in exactlythe same position in an integral outer layer, or shell lined with thewhich it is wound and'prevents the same from looseni or unwind-mg as theprocess is performed. The wires are bound together y this. solder -andform therewith, practically thin sheet metal plate, of cylindrical form,

which may be for instance of very thin material, say or -1; of an inchin thickness. I prefer to apply the solder to the whole surfaceof thewire and to sweat it into the crevices between'the same and into thecrevices or grooves at the interior of the layer of Wire so that thesolder will be applied to the exterior surface of the sheet metal tobind the sheet metal and the wire together.

An important result, follows from the use of the solder in that itsolders the joint where the edges of the sheet metal are broughttogether and thus provides a sheet metal cylinder which would begnaintained in its cylindrical form by the soldered joint alone butwhichin addition to this is sustained and strengthened over its wholesurface by the windingof the wire;

The article as produced by me is particularly adapted for use ascylinders for pumping engines such as the pumping head of oilwells,'-the brass lining providing a wearing surface for the piston towork upon.

By my invention a cylinder may be formed having an accurate borethroughout, as it is only necessary to apply the sheet metal closely tothe accurate y formed mandrel in order to assure accuracy inthe diameterof the cylinder, the wire and the solder serving to maintain the sheetmetal cylinder or interilor lining in exactly the shape of the mandreWhile I prefer to apply the solder throughout the whole extent of thetubing in order to unite the coils of wire to each other and to theinner sheet metal shell, I may apply the solder only to. the portion ofthe wire which overlies the joint of the sheet metal lining. When soapplied the solde'rperforms the two-fold function of uniting the wirestrands .or vcoils together and to the sheet metal lining, and alsoserves to solder the joint between the abutting edges of the said sheetmetal.

The tubing, formed as above described, when used for a cylinder, isprovided with cylinder heads as shown at 1,'having rooves 2 to'receivethe ends of the tube, t e said grooves havin therein suitable packingmaterial 3. he walls of these grooves serve to confine the wire woundends of the tubing and aid in holding the wire in place at the ends ofthe tubing. This effect simply a ments,'however, the holding effect ofthe so der and is not. depended upon. solely to hold the wire in placeat its ends. v The wire wound upon the sheet metal is indicated at 3,the sheet metal at 4, and the joint between the abutting edges at 5.

It will be understood that in carrying out my process I prefer to applythe solder to the windings of wire as the same is laid upon the sheetmetal shell so as to prevent unwrapping and to maintain the wire inprecisely the position in relation to the sheet metal shell in which itis laid.

I claim as my invention:-

1. A cylinder or tubing composed of an inner shell of sheet metal rolledinto cylindrical form with its edges abutting, an outer winding of Wireand solder filling the interstices between the windings of the wireandbetween said wire and the sheet metal, said solder uniting the abuttingedges of the sheet metal together, substantially as described.

2. In combination, a cylinder composed of an inner lining of sheet metalrolled into cylindrical form with its edges abutting, an outer windingof wire soldered thereto and the heads having grooves to receive theends of the sheet metal cylinder and the wire winding, substantially asdescribed.

In testimony whereof, I aflix my signature in presence of two witnesses.

ROSS J. HOFFMAN.

Witnesses:

E. J. Jo Es, KATHARINE BURKE.

